Bottom line: An ounce a day of nuts does not protect against heart disease, despite what this â€śdoctorâ€ť may assert.

I went to the trouble of analyzing some false claims coming out of Dr. Michael Greger on his website nutritionfacts.org. There are really too many to spend time on, so I thought I would just look at the most recent.

I am a retired biology professor who is interested in healthy plant-based diets and have read and followed all the experts over time. Let me say that I eat nuts in moderation as part of my healthy plant based diet, and believe they are a healthy food. I am not "anti-nut" but want to help set the record straight about the relative importance of nuts in a healthy diet. Nut consumption is in no way crucial for good health, despite being so portrayed by the nut industry and their press releases.

I watched Dr. Greger's recent 2-part video presentation today called, â€śHow do nuts prevent sudden cardiac death?â€ť In it, Dr. Greger points out that low levels of magnesium appear to be a marker for heart disease, and that added nut consumption offers potential protection due to the magnesium content of nuts.

The pitch goes something like this: magnesium is important for heart health, post-mortems of people who died of heart attacks all showed low levels of magnesium. A study of vegetarians shows that vegetarians get a bit more magnesium than non-vegetarians, but still less than recommended. Nuts are an excellent source of magnesium, so vegetarians should be adding nuts to their diets to protect against heart disease.

What is wrong with that argument is simply . . . everything.

It has been long known that magnesium is an essential mineral, involved in nearly every function of the body, including the heart. The National Institutes of Health say magnesium is the fourth most abundant mineral in the body and essential to good health. Only 1% of magnesium is found in blood, but the body works very hard to keep blood levels of magnesium constant. For more on magnesium, see this information page on the NIH website: http://ods.od.nih.gov/factsheets/Magnes ... fessional/

Do people who suffered fatal heart attacks have low levels of magnesium? Apparently they do. Why? Because just about everyone in the US population is suffering from magnesium deficiency, since they eat the Standard American Diet (SAD).

Dr. Greger cites a study of vegetarians, which shows that, while vegetarians have higher blood levels of magnesium than non-vegetarians, it is still too low. Those vegetarians need to clean up their diet to prevent heart attacks, he says, starting with nuts.

So let's start by looking at the study cited on vegetarians in the argument. The study is: A Vegetarian Dietary Pattern as a Nutrient-Dense Approach to Weight Management: An Analysis of the National Health and Nutrition Examination Survey 1999-2004

Looking at the study, reviewers compared the diet of 432 lacto-ovo vegetarians to 8,255 nonvegetarians. Both failed to meet the RDA for magnesium.

So what were the vegetarians eating? As you can see when you look at the study itself, they ate a very unhealthy junk food diet.

According to Table 3 in the study, they ate lots of processed grains and little whole grains. (Processed grains contain far less magnesium than whole grains, which are higher.) They ate little fruit, the same amount of vegetables as the nonvegetarians. The vegetarians also ate meat, poultry, fish â€“ seriously! It's all there for anyone to see in Table 3. They ate more eggs, milk and cheese than the nonvegetarians, and they ate more sugar and more oil than the nonvegetarians.

â€¨In other words, the vegetarians in the study ate an incredibly unhealthy diet. Why is this important? Because much of the discussion around nuts in our niche is aimed at people who are already eating much different diets. Most of the discussion around nuts are in places like these discussion forums of Dr. McDougall, Dr. Fuhrman, Dr. Esselstyn, Dr. Barnard and so forth.

So this study of vegetarians who are eating a just slightly better diet than the SAD eaters in no way applies to people eating the kinds of healthy plant-based diets where this issue is being discussed.

â€¨Moreover, if you look at Table 3 of the study, you will see that the vegetarians were eating more nuts than the nonvegetarians â€“ about .89 ounces of nuts a day on average, so almost an ounce serving a day. And yet this did not help them. Dr. Greger and some others advocate an ounce of nuts a day as practically mandatory. And yet the vegetarians, who were consuming almost an ounce per day, were still lacking in magnesium.

â€¨The real problem this study of vegetarians underscores has nothing to do with nuts. The problem is that they were eating only 1.2 ounces of whole grains, which is far below the bare minimum of 3 ounces set by the USDA, and way below the 5-8 ounces which are recommended. They only took in .23 cups of vegetables (non potato) which is way below the recommended 2-3 cups per day. They consumed only .22 cups of beans, which is far below the recommended level.

So the vegetarians in the study do not even meet the minimum USDA standards for a nutrient dense diet.

That is the crux of the issue, not whether these people were eating enough nuts to prevent a heart attack.

If you look at Table 4 of the study, you will see that out of a possible healthy eating score of 100, the vegetarian group scored only 50.5, since they were so low in all fruits, vegetables and whole grains. A typical Fuhrman, McDougall, Barnard or Esselstyn diet would easily score 90 or more.

This study actually shows why Americans (including the lacto-ovo vegetarians in the study) should switch to a healthy plant-based diet, like those of McDougall, Barnard, Fuhrman or Esselstyn. The study does not show why people need to eat nuts. So the issue is not just about magnesium, or any one nutrient, even though Dr. Greger likes to approach diet this wrongheaded way.

But in terms of magnesium, nuts are actually a poor source and score fairly low in regard to nutrient density. To make it appear nuts are good sources of magnesium, Dr. Greger compares foods by weight or volume. But as we well know, using weight or volume to compare foods is an outdated food industry trick and does not give the real picture. The correct comparison is the amount of nutrients per calorie.

The idea of nutrient density and why food should be evaluated by the calorie is that, for example, to get the daily RDA of 400 mg. of magnesium, you can eat 93 calories of Swiss chard, or 857 calories of almonds, including all the added fat. Clearly, the Swiss chard is the better source, not only for magnesium, bur for all other vitamins, minerals and phytochemicals.

As long as you are eating a whole foods plant based diet, with all the whole grains, beans, fruits, starchy veggies and veggies, how mandatory are nuts? You can certainly include nuts. But mandatory? Poppycock.

There is an old saying, that â€śbullsh*t baffles brains.â€ť What it means is you can't just rely on someone making generalizations, mentioning some studies and one or two aspects of what a study says, and then automatically accept their conclusions. That's important if you don't want to get sucked into someone else's agenda.

This is a topic that I am very interested in and a hot button topic that seems to come up frequently on this message board. I appreciate you taking the time to stop by and write about it. It was the main point of disagreement I had with the newest video filmed at a vegetarian conference. Dr. Greger seemed to be saying that including nuts in the diet was essential to good health. What worries me is that many people are eschewing even whole grains in favor of nuts. I replied about this in a discussion about nuts here in The Lounge where I critiqued a new cookbook by True North chef Ramses Bravo, in which nuts were substituted for grains. The dishes were very high calories and high fat. Again thank you for confirming what Dr. McDougall has been saying all along.

Thank you Mark Simon for the great information. That's the exact same conclusion I reached after analyzing the healthy nut claim, just kidding, I had no clue.

I may be naive. But I still believe the truth will be revealed if enough light is shined on the subject.Right now we are dealing with massive ignorance.John McDougall, MD (McDougall Discussion Board, posted 7/2/13)

Dr. Greger performs a service in that he checks out the literature, reports on it and thus brings certain studies to our attention, gives us something to think about and provides the opportunity to review our own health goals. It would be unwise to take everything he writes as gospel without checking other sources and information. Fuhrman has the same opinion as Greger about nuts. Which ought not to cause us to dismiss other things Fuhrman (or Greger) says unless we have checked certain claims for ourselves by reading or asking questions. One might also keep the same attitude with Dr. McDougall since it is possible for anyone to make a mistake, misinterpret or miss a study or two which might show the opposite of what was formerly believed as true.

As for the nuts or any other super food--I tend to agree with Jeff--look at the overall diet.

Yes, I saw the part 2 video today, and it didn't give any additional information about yesterday's, which was titled â€śHow do nuts prevent sudden cardiac death?â€ť This was a very misleading title because nuts do not prevent sudden cardiac death, and the title makes an unfounded assumption that they do.

"How do nuts cure athlete's foot?" Again, there is no evidence that nuts do cure athletes foot, so having a title like that which assumes facts not in evidence and using it to try to imply that they do -- is deceptive. Science and deception don't mix. Thus, I gave your video an F.

It is not providing a valuable service if your information is wrong. It becomes just self-aggrandizement -- the act of making something appear greater than is actually warranted by the facts.

I'm not sure what point you're trying to make. Yes, this is another way to look at the issue, by volume, in addition to by calories. And you can see the same point in your example, that you would have to eat 822 calories (1 cup) of almonds to get significantly less magnesium than you get from eating 105 calories (3 cups) of Swiss chard. So again, nuts are a poor source of magnesium compared to many other foods.

I'm not sure what point you're trying to make. Yes, this is another way to look at the issue, by volume, in addition to by calories. And you can see the same point in your example, that you would have to eat 822 calories (1 cup) of almonds to get significantly less magnesium than you get from eating 105 calories (3 cups) of Swiss chard. So again, nuts are a poor source of magnesium compared to many other foods.

I tend to eat a variety of foods, but I've eaten chard once in my life and rarely eat almonds, so it doesn't matter how much magnesium those have. They won't be a primary source of magnesium in my diet. I like spinach, but I'm not going to eat 3 cups of cooked spinach every day.

Mark,Love your zeal. what scientific information has the low fat gurus provided against nuts? other than they are high in fat, high in calories and noone eats them by handful therefore you are bound to add pounds to your waistline, therefore you should avoid them. As you can see their entire contention rests on lean weight. That can't be called very scientific. can we? Now what is there to prove that if you eat 1-2 oz. of nuts and seeds you are going to be heavier than otherwise you would have been, had you not consumed nuts and seeds? I can add 1 oz of nuts and seeds and maintain about the same weight.

But if you go by the logic and common sense, We know for a fact that all plant foods provide variety of different nutrients and minerals from berries to Banana to Broccoli to Eggplants. That's why the word of wisdom is you eat variety of plant foods and your body will take care of the rest. You will get sufficient quantity of nutrients and mineral. Nuts and seeds are also plant foods. I can add 1 oz of nust and

They grow under sun, rain, cold, heat and in a different tropical environment so I'm sure they bring unique minerals and nutrients in a unique combination to the table just like variety of other plant foods do due to their complex structure, so I won't be surprised they offer unique benefits to the human health.

This may be another way of looking at this very intriguing subject matter.

I tend to eat a variety of foods, but I've eaten chard once in my life and rarely eat almonds, so it doesn't matter how much magnesium those have. They won't be a primary source of magnesium in my diet. I like spinach, but I'm not going to eat 3 cups of cooked spinach every day.

Chard and almonds were merely examples to make a point about nuts as a comparatively poor source of magnesium. If you are eating a McDougall diet, then you are probably eating some whole grains, oatmeal, beans, maybe some spinach, zucchini, kale, berries and so forth. All contain varying levels of magnesium, you should easily be meeting the RDA with your diet.

If we analyzed your diet and you were eating as recommended, we could see which foods were actually contributing the most magnesium, and it would not be nuts -- unless you were eating way more nuts than anyone recommends. So that is the point. Nutrient density is a standard used that makes the most sense.

Chimichanga wrote:

Love your zeal. what scientific information has the low fat gurus provided against nuts? other than they are high in fat, high in calories and noone eats them by handful therefore you are bound to add pounds to your waistline, therefore you should avoid them. As you can see their entire contention rests on lean weight. That can't be called very scientific. can we? Now what is there to prove that if you eat 1-2 oz. of nuts and seeds you are going to be heavier than otherwise you would have been, had you not consumed nuts and seeds? I can add 1 oz of nuts and seeds and maintain about the same weight.

Well I guess the science "against nuts," if you want to put it that way, is simply that yes, nuts can promote weight gain, as you observe. I don't see that as being "against nuts," though.

Nuts are healthy, and I agree that having a variety of foods is desirable. I eat nuts, as I said. Many people are able to eat a lot of nuts and not have any weight issues they want to address. I don't see a reason those people would want to cut back, assuming they are eating a healthy plant-based diet. My central point is that nuts are not a "super food" that can "prevent heart attacks" or otherwise are especially good for your heart, other than when replacing animal products and junk food.

So all in all, nuts are not giving you more cardio protection than the other healthy foods in your McDougall diet. And in fact, there is good evidence that people should look to reduce fats, including nuts, if they are working to reverse heart disease with a healthy plant-based diet.

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